Coil form



0. WlRTH COIL FORM Dec. 11, 1951 Filed July 8, 1949 INVENTOR. 070a? MAM- 2,

BY WW3 & 1PM

f atented Dec. 11, 1951 ooIL FORM Otto Wirth, Zurich, Switzerland, assignor to Micafil A.-G., Zurich, Switzerland 1 Application July 8, 1949, Serial No. 103,585 In Switzerland July 16, 1948 6 Claims.

This invention relates to forms used in the winding of coils for and on the stator elements of dynamoelectric machines such as motors, e erators and the like.

Forms of this general type are in common use in the electrical industry and enable the coil to be wound mechanically in the stator slots it will occupy in the finished machine. The form is first placed in position on the stator adjacent a particular slot; the wire conductor is then mechanically wound round and round upon the form until the required number of turns to form the coilhave been completed; the form is then removed, leaving the coil sides in the slots; and finally the coil heads are bent downward by means of a press. This technique has proven to be quite satisfactory since the conductor is stressed but very little and the coil turns are not distorted on the heads as is the case when the conductor is wound in a bent form. Furthermore, the simpler movements of the conductor guide permit a much higher winding speed.

The object of the present invention is to provide an improved and more simple construction for the form on which the stator coil is wound. One advantage of the new construction is that but very little time is required to .mount the form in operating position on the stator or to remove the same after'the coil has been completed. Another advantage is that the form is held securely in position on the stator while the winding operation is taking place.

A more specific object is to provide a collapsible coil form comprised of a pair of pivotally connected members which may be quickly locked in and unlocked from their extended, coil winding position.

The foregoing as well as other objects and advantages inherent in the invention will become more apparent from the following detailed description of a preferred structural embodiment when considered with the accompanying drawings in which:

Fig. 1 is a longitudinal section of the stator core taken on line l--l of Fig. 2 with the coil form thereon in its extended position for winding the coil;

Fig. 2 is an end view of the stator section and coil form shown in Fig. 1;

Fig. 3 is a view similar to Fig. 1 showing the form in its retracted condition after the coil has been removed; and

Fig. 4 is a plan view of the device.

Referring now to the drawings, the coil form is seen to be composed of two levers I and 2.

Lever 2 is pivotally connected intermediate its ends at 2a to one end of lever l in such manner that the inner end 21) of lever 2 will lie alongside.

and engage the face of lever I when the two levers are moved into coaxial alignment. Because of the double arm, end pivot arrangement. it will be obvious that the axial distance between theouter ends of the two levers is a maximum when they occupy the extended position shown in Fig. 1,- and that this distance decreases when the levers are rotated relative to the pivot 2a to their contracted position shown in Fig. 3.

For securingthe levers l and 2 in their extended position, a wedge type of lock is preferred; the lock including a wedge 3 pivotally secured to lever l and which is adapted to engage horizontal recesses lo, 20, provided in the levers for such purpose.

Depending from the lower side of the levers are two sets of locating pins 4, [5. As is evident from by each of the latter are left and right hand elongated coil crotches 'l and 8. These crotches each include a lower leg la, 8a inclined outwardlyfrom the stator and a horizontal leg lb, 8b, between which the coil I4 is wound. As seen in Fig. 2, the crotch legs la, 8a in plan are of generally triangular shape being broad at the top and tapering downwardly to a small apex at the bottom.

Also depending from the outer ends of the levers I, 2 and at the same angle as the crotch legs la, 8a are rigid extension pieces 9, the lower ends 9a of which are bent to lie horizontally for engage ment by the horizontal offsets Ina at the upper ends of levers in, ID which are pivotally anchored to opposite sides of the stator H for movement in a central plane. Levers l0. ID are coupled in such manner that when one of them is turned inwardly toward the stator the other executes a like movement, and likewise a turning movement of one outwardly causes the other to also move outwardly. The preferred arrangement for effecting the result is constituted by a rod l2 extending from the lower end 01 the left hand lever In (which is pivoted to the stator H at a point intermediate its ends) to an intermediate point on the right hand lever I (the latter being pivoted to the stator II at its lower end below the connection to rod l2). One of the levers such as lever I0 is provided with a handle l3 extending in a generally outward direction from the levers pivot axis to enable both levers to be swung inwardly to engage the lower ends 9a of extensions 9 as shown in Fig. l, or to be swungoutwardly to the disengaged position as shown in Fig. 3.

The manner in which the form is used i believed to be obvious from the foregoing description of its component parts. However, in the interest of assuring a complete understanding of the device, a brief summary of the operating sequence will now be given.

At the start, the two levers I, 2 of the formare first brought to the extended position shown in Fig. 1 and locked in such position by actuating the wedge 3 The extended formi thus placed: on the stator in alignment with an empty slot 5 between the two-slots Iii that are toreceive the coil 14 when wound, the pins 4 engaging the groove and the pins 15 engaging the sides of the stator intermediate the slots. Handle i3 is then swung upwardly to-engagethe ends lfia ofthe levers Ill, lll=with thelower ends 9a ofextensionsfi. When so engaged, thelevers Ill, til! exert a downward pull onthe locked levers l1, 2, thus causing the windingform to be pressed fast against the. body of the stator.

Coil I4 is then wound on theform. by conventionalwinding apparatus (not shown), and the coil for-m havingnow served itspurposecan now be collapsed and removed to. another. slot inthestator. for a repeat operation. To collapse the form requires merely a repetition of the foregoing. procedure. in reversev sequence. That is, handle. i3. is swung downwardly to release the ends oflextensionsiig levers.- l and-.2 are unlocked byreverse motion.of-wedge.,3'; and the levers. are

thencollapsed upwardly about their pivot con-.

nection. sufficiently. to permit. the. extensions. 9 to be.freedfromtheheadsof the wound coil: M;

In. conclusion, while I have: presented a construction for the'coil form which in my opinion.

spiritjand scope of the inventioniasdefined'inthe,

pending-claims.

I claim:

1. A, form for. use in the winding-of coilsimthe.

grooves of the stator element of-selectric enerae tors and thelike comprising. a pair-oflever members. pivotally connected. such that the distance between the outer ends of said-members is extended upon movement thereof to an erectedposi-v tion longitudinally ofthe. stator. grooves with said levers in coaxial alignment, releasable means for; locking said levers in said erected position,

spaced aligning pins depending from said levers; andadaptedto projectinto a firstgroove in said stator intermediate two other grooveswhich are to receive the coil for locating and maintaining said levers in alignment with and over said first slot, and coil guiding members extending transversely of said levers at the outer ends thereof.

2. A coil form as defined in claim 1 wherein a first one of said lever members is pivotally connected intermediate the ends thereof to the end of the second of said lever members, and said releasable means is comprised of a latchmember pivotally secured to said second lever member and slidable into coregistering recesses in said lever members.

3. A form for use in the winding of coils in the grooves of the stator element of electric generaators and the like comprising a pair of lever members pivotally connected such that the distance between the outer ends of said members is extended upon movement thereof to an erected position longitudinally of thestator grooves with said levers in coaxial alignment, releasable means for locking said leversin said erected position, a first set ofaligning pins depending from said levers and adapted to project into a first groove in-said stator intermediate two other grooves which are toreceive the-coil for locating and maintaining said levers in alignment with and over saidfirst slot, a second set of aligning pins dependingfrom said levers and adapted to engage the opposite end faces of said stator for securing-said levers when erected against endwise displacement, andcoil guiding means extending transversely of said levers at the outer ends thereof:

4. A coil winding form asdefined in claim 3 wherein said coil guiding meansareconstituted by crotch members.

5. A coilwinding formas defined inclaim '3'and' which further includes an extension piece dependingfromtheouter'end of'each one ofsaid pairof pivotally connected lever members; when locked in coaxial alignment, and means engageable with said extension'piecesforexerting-a pull thereupon and hence also uponsaid lever members in the direction ofthe-stator 6. A coil winding form as defined in claim 5' wherein said means engageable with said extension pieces is comprised of a pivotally anchoredmember individual to-each-of the pain of *extension pieces, and said anchoredmembers areinterconnected by a tie-rod for effecting-common operation thereof.

OTTQrWIRTH.

REFERENCES" CITED:

The following references are of record'in the file of this patent:-

UNI'IED STATES PATENTS Number Name Date.

11211793" Chapman. Dec. 22, 19.1.4- 2,007,830 McNeil July 9., 19.3.5.

PATENTS.

Number Country Date 223 2'70 1 Germany July '7, 1909 

